Vibrating rectifier.



R. P. JACKSON.

VIBRATING RECTIFIER. APPLICATION FILED. MAY-25. l9l4.

WITNESSES Pzitentd Apr. 1,1919,.

UNITED STATES PATENT OFFICE.

RAY P. JACKSON, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSEELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

VIBRATING RECTIFIER.

Specification of Letters Patent.

PatentedApr. 1, 1919.

Application filed May 25, 1914. Serial No. 840,724.

To all whom it may concern:

Be it known that I, RAY P. JAoKsoN, a citizen of the United States, anda resident of Edgewood Park, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in VibratingRectifiers, of which the following is a specification.

My invention relates to apparatus for transforming alternating currentsinto direct currents, and specifically to rectifying apparatus of thevibrating-armature type.

The purpose of my invention is to devise an apparatus of the characterspecified that will be compact and rugged in construction, and have fewmoving parts, and that also will need no permanent uni-directionalexciting current and will be free from sparking at the contacts, underall load conditions.

Referring to the accompanying drawing, Figure 1 is a diagrammatic viewof my: rectifier, and Fig. 2 is a wave diagram illustrating theoperation thereof.

The mains 3 and 4 of a single-phase alternating current supply circuitare connected to the terminals of the winding 5-5 of an auto-transformer6 having an air gap 7 in its magnetic circuit. A vibratory member 8, ofmagnetizable material, is pivotally mounted at 9 on the core of theauto-transformer 6 and has its upper end disposed within the air gap 7.The center of oscillation and the inertia of the member 8, with respectto the pivot 9, may bepdjusted by a movable counterweight 10, and theamplitude of vibration may be adjusted by springs 11-11.

Since a. rectifier of the vibrating-arlnature type is generally used togiveacomparatively low direct-current voltage for ba' tery charging, Iconnect the secondary or rectifier circuit terminals of theauto-transformer at intermediate points 12 and 13 on the winding 5-5.The point 12 is connected toa fixed contact member 14, and the point13is connected to a fixed contact member 15. Two movable contact members16 and 17 are resiliently mounted, by means of springs 18 and 19,

v on the upper end of the member 8, and are adapted to make contact,respectively, with the fixed contact members 14 and 15. All the contactmembers are preferably constructed from a refractory substance such, forexample, as carbon, platinum or molybdenum. A load, such, for example,as a battery 20 is connected between the mid point 21 of the winding ofthe auto-transformer and the member 8, the latter connection being madeby means of a flexible conductor 22. A fixed winding 23 is mounted tosurround the member 8, although it is not carried thereby, and isconnected across the terminals of the battery 20. Suitable means areprovided for auton'latically opening the cir cuit' of the winding 23upon the flow of rectified current, such, for example, as anelectromagnetic switch 24, The battery 20 may be inserted into orremoved from, the circuit by means of a switch 25.

Having thus described the construction of my rectifier, the operation isas follows: Upon closing the switch 25 and supplying alternating currentto the mains 3 and 4:, an alternating magnetic flux will be set up inthe core of the auto-transformer 6, and a uni-directional magnetic fluxwill be set up in the member 8, the latter being due to the flow ofcurrent from the battery 20 through the winding 23. The interactionbetween the two magnetic fluxes will result in the vibration of themember 8 in synchronism with the frequency of the alternating currentsource. As a result of this vibration. contact will be made and brokenbetween the contactmembers 1 115 and 16-17, respectively. in such mannerthat the alternating current generated in the secondary winding of theautotransformer will be rectified and flow through the wire 22 to thebattery and thence to the neutral point 21 of the auto-trans formerwinding in a well known manner. As a result of this current flow, theelectro mag netic switch 21 will be operated, and the .direct currentflow in the winding 23 will cease, but a uni-directional flux will .con'tinue in the member 8, as will be understood from the followingexplanation. When the contact member 16 is in engagement with thecontact member 14, current will flow from the terminal 12 ofthesecondary winding to the contact member 14, thence to the contactmember 16, member 8, wire 22, battery 20, and point 21, and thence backto the point 12 through the right hand halfof the secondary winding. Theresult of this current flows around through the entire core of theautotransformer, as indicated by an arrow 28. A very considerableportion of this flux will follow the path indicated by the arrow 27because of the fact that, at this time, the member 8 is at the righthand limit of its path of movement and in close proximity to the righthand pole piece of the air gap 7, and

arrow 29. This flux will divide near the. point 9 into a portionindicated by anarrow.

30 and anotherportion indicated by an arrow 31. It will be observed thatthe arrows 27 and '30 point in the same direction, and a unidirectionalflux will flow in the member 8 as'long as the device continues torectify.

If a break between the contact members 14 and 16 or between contactmembers 15 and 17 does not come at the point of zero current flow,indicated by a point 32 on the alternating current wave shown in Fig. 2,sparking will occur. This condition is sometimes encountered because themember 8 does not vibrate in synchronism with the frequency of thealternating current supply, 'which is the same as the frequency of thesecondary winding. The defect may be removed by adjusting weight 10until the natural period of vibration of the member 8 approximates thedesired rate of vibration. When charging a storage battery, the backelectromotive force of the battery, at the beginning of charge, may berepresented by an abscissa 33 in Fig. 2, and the back electromotiveforce, at the end of the charge, by an abscissa 34. The most desirablepoints of'make and break for zero sparking, at the commencement ofcharge, are at 35 and 36, respectively, when the electromotive force ofthe rectified current and of the battery are equal and opposite. Themost desirable points for make and break, at the end of charge are, in asimilar manner, 37 and 38, respectively. It will be observed that point37 is later on the wave than point 35 and that point 38 is earlier onthe wave than point 36. My rectifier automatically provides for thischange in the time of make and break because of the fact that the unidectional flux in the member 8 is variable, being comparatively intenseat the start of charge, owing to the heavy current flow in the rectifiercircuit, and comparatively weak at end of charge, owing to the smallcurrent flow at that time. The force tending to vibrate the member 8will vary directly with the intensity of the unidirectional magneticflux therein, and, as a result, the strong force vibrating the member 8at the commencement of charge will overcome its inertia quickly,throwing it very rapidly over from its right hand position to its lefthand position, for example, bringing about the early point of make 35and bending the spring member 19 to a. marked degree'holding the contactmembers 16 and 17 together for a considerable period and not allowingthem to separate until the point 36 in the alternating wave is reached.In a similar manner, the comparatively feeble force tending to vibratethe member 8, at the end of charge, will cause a late make 37 and anearly break 38.

While I have found these means unusually effective for preventingsparking at the contact members, it frequently happens that, owing tovariations in the wave form or to alterations in the frequency of thesupply current, there will be a tendency to spark at the contactmembers. I greatly mitigate the harmful effects of such sparks byinserting blow-out coils 39 and 40 in the connections to the fixedcontact members 14: and 15, respectively. If an arc tends to hold overbetween the contact members 14 and 16 when the member 8 moves to theleft, the closing of contact between the coin tact members 15 and 17will permit a heavy current flow in the magnet blow-out coil 39 toeffectively extinguish the harmful arc, as shown in Swiss Patent No.42398.

If it is desired to rectify the full voltage of the alternating currentsupply, the fixed contact members 14 and 15 may be connected directly tothe supply mains or they may be connected to any other source ofalternating current having the same frequency as the mains 3 and 4.These 'are obvious changes and would not in any way alter the spirit ofmy invention.

If desired, the rectifier may be started by moving the member 8 by hand,the winding 23 and the cut-out device 24 being entirely done away with.I

Having thus described my invention, what I claim is:

1. In a vibratory rectifier, an auto-transformer comprising a coremember provided with a winding, a portion of the primary and secondarysect-ions of said winding being spaced away from the remainder of saidprimary and secondary sections, rectifying contact members arranged toalternately close a circuit through each portion of Said secondarysection, whereby the magnetic flux traversing each portion of theautotran'sformer Winding periodically exceeds that traversing the otherportion thereof and a pivotally mounted member of magnetic materialarranged in proximity to said core member so as to be traversed by thedifference in the magnetic flux traversing the two winding sections,said member being caused to vibrate by the interaction between said coremember and in turn, causing the relative movement of said rectifyingcontact members. I

2. In a vibratory rectifier, the combination with a winding connectedacross the terminals of a source of alternating current and in inductiverelation to a nearly closed magnetizable core, of a pivotally mountedmember of magnetizable material, one portion of which is free to bevibrated in the gap in the magnetizable core and another portion ofwhich is in proximity to another portion of the magnetizable core, saidwinding being symmetrically disposed on said core with respect to saidpivoted member, two fixed contact members, contact members carried bythe pivotally mounted member and arranged to be oscillated between saidtwo fixed contact members, a connection from said source of alternatingcurrent to one of said fixed contact members, a connection from theother terminal of the ource of alternating current to the other fixedterminal, and a connection from the movable contact members to anintermediate point of the source of alternating current.

In a vibratory rectifier, the combination with an auto-transformerhaving the primary section of its winding connected across a source ofalternating current and having a core member embodying an airgap, of apivotally mounted member of magnetizable material, one portion of whichis free to be oscillated in said air gap and another portion of which isin proximity to another portion of the core member of theauto-transformer, the windings of said auto-transformer beingsubstantially symmetrically disposed on said core member with respect tosaid pivoted member, contact members carried by the pivotally mountedmember and arranged to be oscillated between two fixed contact members,a connection from one terminal of the secondary section of the windingof the autotransformer 'to one of said fixed contact members, aconnection from the other terminal of the secondary section of thewinding to the other fixed contact member, and a connection from themovable contact members to substantially the mid-point of thetransformer winding.

4. In a vibratory rectifier, the combination with an auto-transformerhaving the primary section of its winding connected across a source ofalternating current and havlng a core member embodying an air gap, of apivotally mounted member of magnetlzable material, one portion of whichis free to be oscillated in said air gap and another portion of which isin proximity to another portion of the magnetic circuit of theautotransformer at substantially the mid-portion of the secondarysection of the transformer winding, the windings of saidauto-transformer being substantially" symmetrically disposed on saidcore member with respect to said pivoted member, contact members carriedby the pivotally mounted member and arranged to be oscillated betweentwo fixed contact members, a connection from one terminal of thesecondary section of the winding of the auto-transformer to one of saidfixed contact members, a connection from the otherterminal of thesecondary section of the winding to the other fixed contact member, aconnection from th movable contact members to a neutral point of thesecondary winding section, and means for varying the natural period ofvibration of the pivotally mounted member.

5. In a vibratory rectifier, the combination with an auto-transformerhaving the primary section of its winding connected across a source ofalternating current and havin a core member embodying an air gap, 0 apivotally mounted member of magnetizable material, one portion of whichis free to be oscillated in said air gap and another portion of which isin proximity to another portion of the -magnetic circuit of theautotransformer at substantially the mid-portions of both the primaryand secondary sections of the transformer winding, the windings of saidauto-transformer being substantially symmetrically disposed on said coremember with respect to said pivoted member, contact members carried bythe pivotally mounted member and arranged to be oscillated between twofixed contact members, a connection from on terminal of the secondarysection of the winding of the autotransformer to one of said fixedcontact members, a connection from the other terminal of the secondarysection of said winding to the other fixed contact member, a connectionfrom the movable contact members to a neutral point of the secondarysection of said winding, and means for varying the naturalperiodof'vibration of the pivotally mounted member by varying the location ofits center of oscillation.

6. In a vibratoryrectifier, the combination with an auto-transformerhaving the primary section of its winding connected across a source ofalternating current and having a core member embodying an air gap, of aher and arranged to be oscillated between two fixed contact members, aconnection from one terminal of the secondary portion of the winding ofthe auto-transformer to one of said fixed contact members, a connectionfrom the other terminal of the secondary portion of said winding to theother fixed contact member, a connection from the movable contactmembers to a neutral point of th secondary portion of said winding, andmeans comprising a spring control for controlling the amplitude ofvibration of the pivotally mounted member.

7. In a vibratory rectifier, the combination with an auto-transformerhaving its primary winding connected across a source of alternatingcurrent and having a core member embodying an air gap, of a pivotallymounted member of magnetizable material, one portion of which is free tobe oscillated in said air gap and other portion of which is in proximityto" another portion of the magnetic circuit of the auto-transformer,

substantially one-half the primary and onehalf the secondary sections ofthe transformer winding being magnetically associated with each portionof the transformer core determined by said air gap and said point ofproximity, contact members carried by the pivotally mounted member andarranged to be oscillated between two fixed contact members, aconnection from one ter minal of the secondary portion of the winding ofthe auto-transformer to one of said fixed contact members, a connectionfrom the other terminal of the secondary portion of said winding to theother fixed contact member, a connection from the movable contactmembers to a neutral point of the secondary portion of said winding,means for varying the natural period of vibration of the pivotallymounted member by varying the location of its center of oscillation, andmeans comprising a spring control for controlling the amplitude ofvibration of the pivotally mounted member.

8. In a vibratory rectifier, the combination with an auto-transformerhaving a core member and embodying an air gap, of a member ofmagnetizable material, one portion of which is free to be oscillated insaid air gap, and another portion of which is pivoted upon themagnetizable core opposite the air gap, the windings of saidautotra-nsformer being substantially symmetrically disposed on said coremember with respect to said pivoted member, two fixedcontact members,contact members carried by the pivotally mounted member and arranged tobe vibrated between said two fixed contact members, a connection betweenone terminal of the secondary winding of the auto-transformer and one ofthe fixed contact members, a connection between the other terminal ofthe secondary winding and the other fixed contact member, a connectionincluding a load circuit between the moving contact member andsubstantially the mid point of the secondary Winding, adjustable springsfor controlling the amplitude vibration of the moving member and anadjustable counterweight for controlling its natural period ofvibration.

9. In a vibratory rectifier, the combination with an auto-transformerhaving an air gap in its magnetic circuit, of a member of magnetizablematerial, one portion of which is free to be oscillated in said air gapand another portion of which is pivoted upon the magnetizable coreopposite the air gap, two fixed contact members, contact members carriedby the pivotally mounted member and arranged to be vibrated between saidfixed contact members, a connection between one terminal of thesecondary winding of the auto-transformer and one of the fixed contactmembers, a connection between the other terminal of the secondarywinding and the other terminal of the fixed contactmemher, a connectionbetween the moving contact members and substantially the mid point ofthe secondary winding, adjustable springs for controlling the amplitudeof vibration of the moving member, an adjustable counter-weight forcontrolling" its natural period of vibration, means for generating aunidirectional magnetic field in the mal operation is reached, and meansfor thereafter supplying said member with unl- -action of saidenergizing means when nordirectional magnetic flux by the rectificationof a portion of said alternating flux.

11. In a vibratory rectifier, the combination with means for producingan alternating magnetic flux, of means for rectifying a portion of saidflux and for causing sald rectified flux, in conjunction with saidalternating flux, to drive said rectifier.

12. In a vibratory rectifier, means for rectifying'an alternatingmagnetic flux and for employing said rectified flux in driving saidrectifier.

13. In a vibratoryrectifier, means for producing a rectified magneticflux which varies with the load by the rectification of an'alternatingflux and for employingsaid flux in driving said rectifier.

14. In a vibratory rectifier, ducing a rectified magnetic flux whichvaries with the load by the rectification of an altermeans for pronatingflux and for employing said flux to modify the amplitude of vibration ofsaid rectifier so as to substantially eliminate sparking.

15. In a vibratory rectifier, means for producing a rectified magneticflux which varies with the load by the rectification of an alternatingflux and for employing said flux in driving said rectifier Withdifierent amplisubscribed my name this 18th day of May,

RAY P. JACKSON. Witnesses:

R. W. E. Moons, B. B. HINES.

